1. Field of the Invention
The present invention relates to a vibratory massage device for the treatment of open sore ulcers, lymphoedema and deep vein thrombosis (DVT) as they affect the human or animal body, and a method of treatment of open sore ulcers, lymphoedema and deep vein thrombosis (DVT).
2. Description of the Related Art
It is well understood that three-dimensional vibration (referred to as cycloidal vibration) has beneficial effects in improving blood circulation, joint mobility, and respiratory conditions, and relieving tension. Such vibration is in the frequency range of 15 to 75 Hz with an amplitude varying between 0.1 and 0.5 mm, depending on the orthogonal direction.
Decubitus ulcers are caused by continuous pressure at specific points of the body when a patient is immobile for extended periods of time. It is known that vibration can assist in preventing the development of such sores and U.S. Pat. No. 5,606,754 suggests a bed which has vibration means to reduce the incidence of bed sores.
Ulcers are caused by underlying blood circulatory problems, either venous or arterial disease. If the venous system in the leg fails to work normally, the pressure in the leg veins rises. This reduces circulation in the lower leg and leads to swelling and discomfort. The skin changes and becomes vulnerable and is poor at healing. A small injury, bite or minor infection, that would normally heal quickly, instead progresses and an area of skin break down results in the formation of an ulcer. Varicose veins, a previous deep vein thrombosis, or primary failure of the valves in the veins can all contribute to ulcers.
The current method of treatment is to cover the affected skin area with a dressing, in order to keep the skin moist and prevent infection from entering the sore, and to immobilise the sore in order to facilitate healing. However, some patients suffer from venous ulcers for extended periods of time in the order of months or even years before they heal, if ever. There is an evident need for more efficient treatment of ulcers.
U.S. Pat. No. 5,948,009 discloses an ablation electrode for treating canker sore in which vibratory massage is applied to create a lesion. This is said to create the conditions for subsequent healing.
Lymphoedema is the chronic swelling of subcutaneous tissues due to the accumulation of excessive lymph fluid. The accumulation of lymph fluid results from impairment to the normal clearing function of the lymphatic system and/or from an excessive production of lymph. Lymphoedema is divided into two broad classes according to aetiology. Primary lymphoedema is a relatively uncommon, chronic condition which may be due to such causes as Milroy's Disease or congenital anomalies. Secondary lymphoedema, which is much more common, results from the destruction of, or damage to, formerly functioning lymphatic channels, such as surgical removal of lymph nodes or post radiation fibrosis, among other causes.
Current common treatments include manual lymphatic drainage (a form of skin massage), exercise program and a form of compression bandaging. However, pneumatic compression therapy is also used, although proof of its effectiveness is lacking. Indeed, care needs to be taken to avoid forcing fluid too rapidly from the limb to adjacent parts of the body.
Deep Vein Thrombosis (DVT) refers to the formation of a thrombus (blood clot) within a deep vein, commonly in the thigh or calf. The blood clot can either partially or completely block the flow of blood in the vein.
Compression therapy is used to aid circulation to prevent patients at risk of clotting from developing DVT. Likewise, pneumatic compression therapy is used on patients at risk of DVT and this treatment is often used prior too and after surgery, especially limb surgery such as knee surgery and joint replacement where the risk of DVT is often greater.
P Lievens, A Leduc and J Dewald presented a paper under the title “The Use of Cycloidal Vibrations Therapy on Blood and Lymph Circulation and on Wound Healing”, at the VII International Congress of Lymphology, Firenze, Italy 28 Oct. to 2 Nov. 1979. In that there was a suggestion that some aspects of wound healing in test mice were improved by a regime of cycloidal vibrations. However, nothing has come of that work and its teaching is limited.
Also, A J Pickup, S Alexander, and R G Gosling presented a paper under the title “The effect of cycloid vibration on leg blood flow and ulcer pain” to the Section of Dermatology of the Royal Society of Medicine in 1978. While vibration was recognised to dramatically reduce pain from leg ulcers, only a slight improvement in healing was noticed.
It is an object of the present invention to provide an improved method of treatment of ulcers, and also lymphoedema and deep vein thrombosis.
In accordance with a first aspect of the present invention there is provided a method of treatment of ulcers of the human or animal body, which method comprises the step of subjecting the body in the area of the ulcer to mechanical vibrations for an effective period of time, said vibrations having a frequency of between 15 and 75 Hz, and an amplitude of between 0.1 and 0.5 mm.
In accordance with a second aspect of the present invention there is provided a method of treatment of lymphoedema of a patient, which method comprises the step of subjecting the body in the area of the lymphoedema to mechanical vibrations for an effective period of time, said vibrations having a frequency of between 15 and 75 Hz, and an amplitude of between 0.1 and 0.5 mm.
In accordance with a third aspect of the present invention there is provided a method of prophylactic treatment of deep vein thrombosis, which method comprises the step of subjecting the body in the area of the thrombosis to mechanical vibrations for an effective period of time, said vibrations having a frequency of between 15 and 75 Hz, and an amplitude of between 0.1 and 0.5 mm.
The cycloidal mechanical vibrations are provided by a treatment device that delivers mechanical vibrations at its surface in three orthogonal directions at a frequency in each orthogonal direction of between 0.1 and 0.5 mm. The device may have a pad connected thereto. The step may further comprise the application of pressure against the limb. This pressure may be applied by a pressure applying means so that, in use, the device delivers vibrations in the limb of the patient at a frequency of between 15 and 75 Hz, and with an RMS acceleration in the axial direction of the tibial or fibulal bone of between 5 and 15 ms−2, and in a radial plane with respect to the tibial or fibulal bone with an RMS acceleration of between 2 and 5 ms−2.
Preferably, said vibrations have, in each case, components in three orthogonal directions, said frequency being the same or different in each direction, and said amplitude being the same or different in each direction. Preferably said period is more than fifteen minutes, ideally about thirty minutes. The treatment is preferably repeated three times a day.
Preferably, said treatment is applied by a vibratory device comprising a pad, and said method also involves the application of pressure by the pad against the tissue of the patient. The pad is preferably a cushioned frame fixed to a vibratory drive unit.
In another aspect, the present invention provides an ulcer, lymphoedema and deep vein thrombosis treatment device comprising:
a drive unit adapted to deliver mechanical vibrations at its surface in three orthogonal directions at a frequency in each orthogonal direction of between 15 and 75 Hz and with an amplitude in each orthogonal direction of between 0.1 and 0.5 mm;
a pad connected to said drive unit; and
pressure applying means by which the pad may be pressed against the limb of the animal or human.
Preferably, said pressure applying means comprises a strap by means of which the pad may be secured to said limb. Indeed, preferably, the area over which a given level of pressure in excess of 1333 Pa (10 mmHg), preferably 2666 Pa (20 mmHg), is applied to the limb by the pad is increased by at least 25%, preferably 50%, by application of said pressure applying means.
Preferably, the drive unit is substantially cylindrical. It may have a casing mounting a motor having an armature parallel the axis of the cylinder. The motor may drive an eccentrically mounted weight to provide oscillations of the casing in a radial plane. The motor may be mounted through flexible mountings in the casing so that a component of the vibration is created in an axial direction of the armature.
In another aspect, the invention provides the use of a drive unit and a pad in the manufacture of a device for the treatment of an ulcer, lymphoedema or deep vein thrombosis of a patient, wherein said drive unit is adapted to deliver mechanical vibrations at its surface in three orthogonal directions at a frequency in each orthogonal direction of between 15 and 75 Hz and with an amplitude in each orthogonal direction of between 0.1 and 0.5 mm, and wherein said pad is connected to said drive unit.
GB-A-2096899 describes a conventional analogue control of a universal AC motor for a vibration device, which control is found not to provide a smooth delivery of power to the motor so that, at some frequencies, the three-dimensional nature of the vibrations is lost.
Preferably, therefore, the motor is electrically powered from mains AC electricity, the drive unit including digital control means to ensure smooth supply of energy to the motor.
Said digital control means preferably comprises:
a detector for each zero crossing point of the AC power supply and adapted to disconnect power from the motor when said crossing point is detected;
a timer comprising a counter started by said detector;
a comparator to compare the count of said counter with a number stored in a memory and to switch power to the motor when said count equals said number.
Preferably, a low voltage transformer is disposed between the power supply and detector. A rectifier may convert the power supply to the motor to DC, if the motor is a DC motor.
Preferably said number is adjustable to vary the power supplied to the motor, and hence its speed of rotation and hence said frequency.
Preferably said counter is capable of providing about 250 counts in each half cycle of the power supply.
Preferably the drive unit operates at a frequency of between 30 and 60 Hz.
Said pad preferably comprises a rigid frame connected to said drive unit and through which mechanic vibrations are transmitted, and cushioning overlying the frame.
When the method above employs the device provided by the present invention, the pad is applied by said pressure applying means to the leg of a patient suffering from ulcers, lymphoedema or deep vein thrombosis and so that, in use, the device delivers vibrations in the leg of the patient at a frequency of between 20 and 50 Hz, and with an RMS acceleration in the axial direction of the tibial bone of between 5 and 15 ms−2, and in a radial plane with respect to the tibial bone with an RMS acceleration of between 2 and 5 ms−2. The acronym RMS is well known in mathematics, science, and engineering for the “root mean square.”
Preferably, the device delivers vibrations in the leg of the patient at a frequency of about 30 Hz, and with an RMS acceleration, in the axial direction of the tibial bone, of about 10 ms−2, and, in a radial plane with respect to the tibial bone, with an RMS acceleration of between 2 and 5 ms−2.
Despite the apparent contrary indication that movement will unsettle the healing of venous ulcers, it has been discovered that cycloid vibrations have a beneficial effect on their healing, and that this healing is dramatically improved by the application of pressure against the tissue of the patient by the cushioned pad that is delivering the vibrations. Without being reliant on any particular theory, this beneficial effect may be due to improved blood circulation caused by the vibrations and increased moisture in the upper dermis and epidermis. Indeed, the healing effects of the present invention are especially felt when two features of the invention are fully exploited. The first is the three-dimensional aspect of the vibration; some benefit is experienced with two-dimensional vibration but significantly enhanced effects have been noted with three-dimensional “cycloidal” vibration, particularly when employing the motor control described above which provides smooth power delivery to the motor. The second is the pressure applying means, which serves to unite the patient's limb with the device and ensures deep transmission of the vibrations into the flesh of the patient. This is particularly the case given the cushioned pad, which of course tends to dampen vibration. By pressing the pad against the patient's leg, the area of contact is increased and this enhances the transmission of vibration throughout a greater volume of the patient's tissue. Together with effective motor control limiting the appearance of transient spikes and the pressure applying means spreading the application of the vibrations, more intense vibrational treatment is possible without exceeding the comfort threshold that patients encounter as the intensity of vibration is increased.
Furthermore, the invention also provides a device as described above further comprising a detachable cover for the pad and drive unit. Said cover may comprise an open pouch to receive said pad and drive unit, fastening means to close the pouch about the pad and drive unit, openings in the cover being provided to permit cooling airflow into the drive unit.
Said cover preferably comprises a deep pouch to receive the pad, and a flap on a front side of the pouch extending from the lip thereof and having a first fastener along its edge remote from said front lip and adapted to detachably fasten to a second fastener along the lip of the pouch on its rear side, two of said openings thereby being defined between each free edge of the flap and the lip of the pouch between its front and rear sides respectively.
Preferably, one of said fasteners comprises a strip of hooked material while the other comprises a strip of hooped material, so that pressing said materials together effects a releasable connection.
Preferably, the cover is of impervious material to prevent liquid from penetrating and contaminating a pad received within the cover.
Preferably, a strap is integrally formed in the cover. Indeed, there may be two straps spaced along the pouch so that, if one is in the area of the ulcer of the patient when the patient's limb is located appropriately with respect to the pad, it can be left undone. When the other strap is secured, this applies sufficient pressure to provide the improved vibration transmission.
Preferably, the or each strap is sewn at one end into a side edge of the pouch and at its other end is provided with a third fastener, the other side edge of the pouch being provided with a complimentary fourth fastener.
Preferably, the fourth fastener extends along the length of the pouch to vary the possible disposition of the or each strap when the third and fourth fasteners are engaged.
The third and fourth fasteners may comprise hooped and hooked fabric material. Indeed, the fourth fastener may comprises a strip of such material along a significant part of the length of the side edge of the pouch so that the or each strap can vary in its position of attachment to the other side of the cover.
The cover serves to protect the pad from contamination from weeping and ulcers. Such weeping tends to occur when they are treated in accordance with the present invention.
In another aspect, the cover may comprise a simple sheet of material having means to gather its edges on an underside of the pad of the vibratory device, and render the sheet taught on an operative side of the pad against which a patient's limb is intended to lie. At least one hole is preferably provided in the sheet to permit the drive unit to protrude through.
The cover may comprise means to fasten a strap to the cover, and hence to the pad, for the purpose of providing said pressure applying means. Said strap fastening means may comprise strips of hooked or hooped material along the sides of the cover to which a strap of respectively hooped or hooked material may be fastened.
Indeed, in another aspect, the invention provides a cover for a vibratory massage device as defined herein, the cover being as defined above.
Furthermore, the invention provides a kit of parts, comprising a cover and a strap, and, in its simplest form, this may comprise a simple sheet suitable for protecting the pad, and a strap suitable for applying the requisite pressure when securing a patient's limb to the pad.